SO fiddle

Test Fiddle mainly for SO Questions

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<input type="text" id="StreamUrl" />

CSS

input { width: 300px; }

JavaScript

$("#StreamUrl").keyup(function (e) {
  $(this).val(function(i, v) { return v.replace(/ /g,"-"); });
});